Pharmaceuticals and foods are usually packaged in the following manner. That is, a base material is made by forming a plastic sheet into a sheet having pockets, contents are put in the pocket portions, and an aluminum foil cover coated with an adhesive is allowed to adhere to the flat part of the base material other than the pocket portions by heating, etc. This package is called PTP. The aluminum foil is broken through by pressing the pocket portions of the base material by fingers to take out the content. Thus, this packaging is very convenient and widely used.
However, in the conventional PTP, the cover material comprises an aluminum foil (inorganic material) and the base material comprises a plastic (organic material), which utterly differ from each other. Therefore, they must be separated after use, and it is very difficult to perform recycling or incineration of them after use. Under the circumstances, it has been desired to use plastics also for the cover material in place of the aluminum foil. However, usual plastic sheets are too strong as cover materials, and lack push-through property in use (when the content is to be taken out). The push-through property here means easiness to break the cover material adhering to the base material in taking out the contents such as tablets which are packed in the pockets of the base material formed by molding. For imparting the push-through property to plastic sheets, there is a method of filling the sheets with fillers such as inorganic fillers, but if the particle size of the fillers is large, the appearance of sheets becomes rough to cause sometimes non-uniformity of the push-through property.